GTA02 RTC backup battery

From Openmoko

RTC keeps the current time while Neo FreeRunner is off or suspended. Rechargable lithium backup battery should keep clocks running for hours when main battery is flat or removed, but it has limited lifetime.

Alternatives - untested:

(search digikey.com) ? What terminal type?:

DSK-3R3H224 (1000 Hrs @ 60°C)

KS-3R3224 (1000 Hrs @ 70°C)

EDLEN204 (1000 Hrs @ 85°C), Long Life - 15 years Datasheet quote: "...Temperature Factor. To determine the effect of temperature on expected life of a supercapacitor, use the fact that expected lifetime doubles for each 10 °C that the operating temperature is reduced. As an illustration, at 85 °C and full voltage the rated lifetime is 1000 hours. So, at 40 °C the expected lifetime would be multiplied by 2^((85-40)/10) = 2^4.5 = 22.6 times. The Temperature Factor is 22.6, and for 1000-h, 85 °C rated life, the expected 40 °C life would be 22600 hours..."

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RTC keeps the current time while Neo FreeRunner is off or suspended. Rechargable lithium backup battery should keep clocks running for hours when main battery is flat or removed, but it has limited lifetime.

Alternatives - untested:

(search digikey.com) ? What terminal type?:

DSK-3R3H224 (1000 Hrs @ 60°C)

KS-3R3224 (1000 Hrs @ 70°C)

EDLEN204 (1000 Hrs @ 85°C), Long Life - 15 years Datasheet quote: "...Temperature Factor. To determine the effect of temperature on expected life of a supercapacitor, use the fact that expected lifetime doubles for each 10 °C that the operating temperature is reduced. As an illustration, at 85 °C and full voltage the rated lifetime is 1000 hours. So, at 40 °C the expected lifetime would be multiplied by 2^((85-40)/10) = 2^4.5 = 22.6 times. The Temperature Factor is 22.6, and for 1000-h, 85 °C rated life, the expected 40 °C life would be 22600 hours..."